Dynamo



1,517281 L. B. EHRLICH DYNAMO Dec. 2, 1924.

Filed Jan. 28. 1924 INVENTOR Louis B.EHRUOH A'ITORNEY Patentetl Dec. Z, 1924.

' UNITED STATES PATENT OFFICE.

LOUIS B. EHRLICH, OF BROOKLINE, MASSACHUSETTS, ASSIGNOR T0 GRAY DAVIS, INC., OF CAMBRIDGE, MASSACHUSET'IS.

DYNAMO.

Application filed J'anuary 28, 1924, Seria1 N0. 688,966.

wlxere provicled, tl1ecarrier-ring for an-- qularly adjusting one o1 1nore of the brusl1 holders.

lVhere the endcap was of cast iron, it was customary to machine a flange for sup porting tl1e carner-r1ng, ancl wlxere 1 was of sl1eet melal, 1t was oustomar v to r1vet or otl1erwise fasten such a flangze to lt. My ln-' vention compreloencls the nse 0f a Tube fo1' tliis purpose fixecl, as by a press fit in ehe l earing nose of tl1e encloap und having innor and outer surfaces concentrio with tl1at flange of tl1e endcap filmt fits tl1e fielcl fran1e, so tl1at \vlien ll1e carrier-ring is tnrned 011 the tube f01 angular arljustment. tl1e one or more brush h0lclers carrietl lrr ehe carrier ring retain tl1eir angle aml arm of contact wifh tl1e commutalor willxout chauge. wlxielr is of utmost importance particularly in thir l lo111sl1 generator of tl1e small size usual l'or automoloiles. T0 furtl1er assist in 1naintaining tl1is condition, the endcap rnay have a flaf annular surface on its insicle acljacent fl1e bearing nose, againstwhich is l1elcl b v suitable means tl1e flat annular suriace 011 tl1e carrier-ring, ancl tl1e carrier-ring may also have a bearing flange fitting tl1e tul e By splitting tl1e carrier-ring ancl giving it adiameter which when unrestrai'necl is slightly less than the diameter of oho tuloe, a tight turning fit is readily obtained in all adjustecl positions, particularly when of pressecl-up sheet metal. Tl1e angular adljustment of tl1e carrier-ring is provided by stamping out gear teeth in its rim and having a pinion meshed therewith.

In any of tl1e fbregoing constructions, I

may providlo a spring which not only holcls the carrier-ring again'st tl1e endcap, but also or oonstm ction, I p1eler l1olds the pinion in mesh with the gear teeth, the pinion ancl tlie spring being sup port-ed by tl1e enrlcap. Also, for clrawing up and holding the enclcap to tl1e limit of its seat 011 tl1e field fra1ne, I may provide a plurality of bent stay wires whicl1 are fastened to the fielcl frame ancl to tl1e endcap ancl which have adjustable 1neans f01fl ehe purpose.

Irrespective of the construction of the enclcap 01' of the carrier-ring, my invention also comprehencls a pressed-up sl1eet-metal brush holder of tl1o swinging arm type, havingr a web portion integral with siclo flanges and an end flange to combine lightness Wllll rigiditjn The encl flange l1as a fiat outer portion so abut the face of a brusl1, so as eo provicle suflieient contact area therewith, anrl the sicle flanges terminate at Ehe otl1er end in ears having holes for bearings for the brush holder Stutl. Pre ferably theintermediale portion o1 the sicle flange is of lesser heiglxt than tl1e ears o-r the end flange,

anrl 1nerge tlxereinto, so as to provi le more space above ll1e brusl1 holder witl1out sacrificing strength. Also the web portion may l1ave a oup-shaped protrusion whicl1 is screw threarled, tlms furtl1cr adrllng; to tl1e' strength or' tl1e brusl1 holder und also provi tling for a screw for a connecting lead.

Vl1ether tl1e brush holder is of sl1eet 1netal 01' is buill up, 011 l1as any other form lo provirle it Willi means lor lifting tuhe l rusli spring fron1 tl1e spring posl at a prerleterminerl angulnr position ol' tl1e bruslm holder on irs stucl. so that When tl1e lorush l1as worn to its predeterrninecl liinil it antomatically loses its efl'ective contact witl1 l'll eollector or commutacor, this result prelerably being obtainecl b v accorrlinpgly constrncting t-he web portion of l'ho brush holder.

In the accoxnpanying draufings illustrating tl1e application of my invention, as an example, to a four-pole thircl brush generator having lall bearings and an angularly acljustable thirdl brusl1,

Fig. 1 is a view representing in parta section on line 11 of Fig. 2 in part broken away and in part in elevation; Fig. 2 repre sents a longitudinal sect io1i partly in elevation, of thecommutator end 0f the generator; Fig 3 represents an elevai;ion of the inside of the endoap; Fig.- 4 is similar to Fig. 3 -exrept tho carrier-ring is for the opposite direction of rotation; Fig. 5 re presents a section 011 line 5-5 of Fig. 6; F1g. 6 represents, partly in elevation and partly in section, the carrier-rinp; W11l1 its brush holder; and Fig. 7 represenlss a detail of one of the stay wires.

The field frarne 1 has four pole pieces 2 Wound with field coils 3. The armature 4 und commutator 5 are mounted on the shait 6 for rotation in the field frame in the ball bearing 7 at one end and a similar ono at the other end (not shown).

The endcap 8 is of pressed-up sheet stoel having a peripheral flange 9 with its end portion 10 tightly fitting 21 seat around tho end 0f the field frame. und being drawn up to the limit thereof, as shown hast in Fig. 7, by means of two stay Wires 11 diametrioally opposite each other. Each has a head 12 oountersunk in a hole in the field frame, and a screw threaded end which is engilg'ed. hy a nipple 13 countersunl: in the ondczip fo1 tightening from the outside. The endoap also has a bearing noso 14 at its central portion and around its peripheral flange a plurality of openings at 15 covered hy the usual qarter strap 16. Inside the endcap is 21 flaf; annular surface 17 adjacent the bearing; nose.

A tube 18, projecting inwardly beyond the flzub surface 17, has a press fit in the bearin s: nose to fix it therein and has a cucout at 19- reaistering with the oiler 20. The inner und outer surfaces of the tube ore concentric with the end portion 9 o1 the neripheral flange and at ri;zht anales to the Hat surface 17. this being accomplished loy machining those surfaces in a single set-np with the Tube in place. -The outer race 21 of the ball hearing is then fixed in the tube b v a snction fit, and the inner raoe 22 is prcssed on the armature shaft 6, so that the shaft is supported at that end and also m3 tho other end to maintain the armature aml comrnutator concentrio With the maohined surfaces of the tube and field frame. The felt. washers 23 and 24 prevent the entrance of dust into and the loss of oil frorn the ball bearing 7. The retainers 25 and 26 hold the washer 24 in place.

The carrier-ring 27 is of pressedmo sheot steol having a. bearing flange 28 und a periphoral flanzre 29 opposite the flat annular surface 17 of the endcap. Both flanqes are snlit radially at 30 and the inner diameter of the bearing flange is, when unrestrained, about .005 inch less in diameter than the outside surfaceof rhe tube. so that when pressed on the tube, it fits tightly and yet is thereon.

The peripheral flange 29 has qenr teeth 31 stamped from its rim. The pinion 32 has an infeorral extension 33 proiectin,q through the endcap for support thereby and has a screw'- driver slot for turning it from tho outside.

This pinion is hold against the inner face of the endcap in mesh With the gear teeth 31 by pressure of a spring plate 34 fastened to the endcap by the screw 35. The two struckup nibs 36 of the spring plate also bear against the carrier-ring 27 to hold its annular surface in intimate contaot with tl1e flat annular surfnce 17 015 the endcap assisted diametrically opposite by an identical spring plate 37. Thus when the pinion is turned, the onrrierring is turned on the tube to .1djust the third brush in angulor position with respect to tho main brushes, the 1novemont heing, limitod in both directions by tho terminal goar teoth.

The oarrier-ring 27 also has an extension 38 fo1 supporting the brush holder stud 30 and the spring post 40. The sind is rivotod in the oarrier-ring with insulating washers und a tube 150 insulate it therofrono, und the spring post is riveted into the carrier-ring und carries an insulating sleeve 41, as shown hest in Figs. 5 and 6. Two brush holders 42 a.nd 43 are similarly mounted 011 studs riveted to tho ondcap and insulated therefrom loy insulating washers and an insulaling tobe. So also, euch has a spring post riveted to the endcap and carrying an insolatingr sleere. The brush holder 43 .is grounded 011 Ehe endcnp by the oonnecting lead 14- and clip 45.

The hrush holdors 42 and -18, 1or the 111:1h1 hrushes 16 und 47. are supported directly by the endcap. and fhe hrush holder 18 for tho thhd hrush 49 is fixed to tho angularly ad justahle carrier-ring supported by tho endcap. They are identical in construction except filmt 21s shown tho main brushes :1re thicker than alle third brush. Euch brush holder is n1ado of pressed-up sheet stoel huv ing a weh portion 50, two side flanges 51 und 52. and an end flange The Web portion has a cup-shnped protrusion 54 which is scrmv threaded to recoive .1 sorew 55 lor seourinq a connecting lend theroto. Euch of the side flanrres has an intermedizxto portion 56 mergin.q into'lhe end flanoe 53 ut ono end und into tho ear 57 at the othor end and hoing of lessor height than either to pfovide for the stav wires 11 without sacrificing rigidity. The end flnnge 53 has o flat outer snrface which is hold in intimato contzwt with the hrush by screws 59 and 00 screw threaded into the clzunping platte 61. Tho ears 5 have hearing holes to receive tho studs 39, the brnsh holder being prevented from mox*ement 011 the stud by the spring rinq 62.

As shown hast in Fias. 5 und 6. a doublo coil hrush spring 63 is housed hetweon the ears 57 and coiled around the stud 39 hining its two ends 58 pressinq against the weh portion 01 the brush holder. und its central portion 58 DI'QSS1I1Q; against the insulated roller 41. The web portion of each b1ush holder extends np in a curveto an end 64: which is so oonstructed andarranged tl1at at a predetermined angnlar osition of tl1e brush holder 011 the Stnd, the spring is lifterl olf the insulating roller and the pressnre 011 the brusl1 holder is ren1oved. 'Ihns when the b1nsh is worn down in operation to its predeter1nined limit, as indicatjed in tl1e case of brnsl1 47 in Fig. l, it is 110 longer hold in operative contact Wlth the connnutator.

'Ihe brnsh holders 111ay be reversed 011 their stncls for tl1e opposite direction ol rotation of. the arn1ature, the carrier-ring being replaced by one otherwise the same hat adapted therefor, as shown in Fig. 4.

Having thus described my invention what I elaim is: 1

1. In a dynan1o el ectric machine, a field fra1ne, an armatnre and oomn1utator arranged for rotation in the field frame, an endcap hiwing a flange fitting the field frame and having a bearing nose, a tnloe fixed in the bearing nose and having inner and onter surfaces concentric with said flange, a carrier-ring tightly fitting 011 said outer surfaoe of the tuhe, a brush holder oarried by the carrier-ring' for cooperatioh witl1 the commutator, and means for turnlng the carrier-ifing to adjusted angular position 011 the tube.

2. Ina dynamo eleotric machine, a Held frame, an armature and oommutanor arranged for rotation in the field frame, an endcap having a flange fitting the field frame and having a bearing nose and also having a flat annular snrfaceon the inside adj acent the hearing nose, a tobe fixed in the hearing nose and having inner and outer surfaces ooneentric witl1 said flange, a carrierring tightly fitting on said onter surfaoe of the tube and having a flat annnlar surface opposite the flat annular surfaco of the endcap, a brush holder oarried by the earrierring for cooperation with the co1nmutator, means for turning the oarrier-ring to adjusted angular position on the tnbe, and means for holding said annnlar snrfades in contact in all adjusted positions of the Carrier-rin n 3. In a dynamo electric n1achine, a fie1d frame, an arnaature and oonnnutator arranged for rotation in the fie1d frame, an endeap having a flange fitting the field frame and having a beairing nose and also having a flat annnlar surface on the inside adjacent the bearing nose, a tube fixed in the bearing nose and having inner and oufier surfaces concentric with said fiange, a eurrier-ring having a bearing flange tightly fiting around the unter surface of the tuloe and having a flat annular rim opposite the flat y annular surface of the endeap, a brush holder carried by the carrier-ring for cooperat1on W1th the commutator, means :for turning the carrier-ring to adjusted ang'ular position on the tobe, and means for holding said annnlar ri1n in contact with the annular snrfaoe of the endcapin all adjusted positions of the carrier-ring.

4:. In a dyna1no eleetrie maohine, a field frame, an ar1nature and commutator arranged for rotatlon in the field frame, an endcap carried by the field fran1e and having an ar1nature bearing and asnpport, a, Carrier-ring which is split and has a diameter which, when unrestrained, is sligholy less than the dia1neter of tl1e support so as to fit tightly thereon for tnrning, a brush holder oarried loy the carrier-ring for cooperation with the commutator, and means for tnrning tl1e carrier-ring to adjusted angular osition 011 th e support.

5. In a dynamo electrio machine, a field frame, an armature and commutator for 1'0- tation in the field fra1ne, an endcap carried by the field fra1ne and having an arn1ature bearing and a support, a pressed-up sheetmetal oarrier-ring having a bearing flange tightly fitting tl1e snpport and an annularrim having gear teeth, said flange and rim helng split, so that when unre strained the flange is of slightly less diameter than the support, a brush holder carried by the sarrier-ring for cooperation with the commutator, and a pinion meshed with said gear teeth to turn the ci1rrier-ring to adjusted angular position 011 the support;

6. In a dynamo electrio maohine, a field frarne, an armatnre and commutator arranged for rotafiion in the field frame, an endcap carried by the field frame and having an arnoatnre bearing' and a Support, a oa'rrier-ring mounted 011 said support and carrying gear teeth, a pinion supported the endcap in mesh With said gear teeth. to onrn the carrier-ring to angnlarly adjusted position 011 the support, a spring fastened to the endplate and pressing against tl1e earr1er-r1ng and the p1n1on to ma1nca1n the oarr1er-r1ng aga1nst the endcap and the pn1- 1011 meshed with said gear teeth in all adv jnsted positions of tl1e carrier-ring, and a brnsh holder carried by the carrier-ring for cooperation with 4 tl1e cOmmntator.

7. In a dynamo eleetrio maohine, a field frame an arma ture. and commutator arranged for rotation in the field frarne, a

prossed-p sl1eet-mecal endcap having aflange Witl1a cylindrical seat fittlng aronnd the field frame and also having a bear1ng the 'carrier-ring for adjusted annular position 011 the tobe, and n1eans for holding said annular snrfaces in contact in all adjusted positions of the carrier-ring.

8. In a dynamo electric machine, a field frame, an arn1ature and commutator arranged for rotation in the field frame, a pressed-up sheet-metal endcap having a flange witl1 a cylindrieal seat fitting around f-he field lrame and also having a bearing nose und also hai'ing a flat annular surface 011 the inside adjacent the bearing nose a Tube fixed in the bearing nose and having inner and outer snrf1ces conoentric with said cylindrical seat, a pre'zssed-up sheet-metal varrier-ring having a bearing flange tightly fittinp; the tube and having.an annular rim with gear teeth, said flange and rim being split so that when unrestrained the flange is of slightly less diameter than the tube a brush holder carried by the carrier-ring :for cooperation with the co-nnnutatm, a plurality of brush holders carried b v the endcap a pinion supported b;v the endcap and Ineshed With said gear teethto tnrn the 021rrier-ring to adjusted position on the tobe, und rneans for holding said annular ri1n in contact with the annular surrace of the endcap and l"0r holding tlie pinion in mesh with the gear teeth in all adjusted positions of tl1e carnennng.

9. In a dynamo electric n1adhine, a field fran1e, an armatnre and collector arranged for rofation in the field .frmne, a pressednp Sheet-1netal endcap having a flange with a c vlindrical seat fitting around the field fran1e and also having an armature bearing, a plnrality 0'lt' brushes supported by the vndc2lp, and a plurality of bent stay wires Which are fastened to the field frame and to the endoap and Which have adjustable means 'for drawing the endcap "ro the limit of its seat on tho field fra1ne.

10. In a dynamo elecfrio 1nachine, an endoap, and a pressed-np sheet-1netal brush holder oli the swinging arm ty pe supported b v the Cndcap und having a web portion integral with side flanges and an end flange, said web portion h'avin a cup-shap6d protrusion which is screw threaded, said end flange lniving a flat outer Portion to ahnt the -face of a brush, and said side fianges terminating at the other end in ears having holes to form bearings for a brush-holder stud.

11. In a dynamo eleotrio machine; an endcap; and a brush holder of the swinging arm type suppofled by the endcap, a stud forming a pivot for tl1e brush holder, a post, and a spring pressing against the brush holder and the post, said brush holder being C011- structed und ananged to lift the spring fro1n the post when the brush holder reaches a predetermined angular position on the stud.

12. In a dynamo electric machine; an endcap; and a brush holder of the swinging arm type supported by the endcap and haVing a web portion and side flanges, a stud forming a pivot for tl1e brush holder, a post und a spring pressing against the brush holder und. Ihe post, said web portion being constrncted und arranged to lift the spring fro1n the post when the brush holder reaches a )redeterrnined angular positiou on ehe sind.

13. In a dynamo electric machine; an endrap; und a pressed-up sheet-metal brush holder or" the swinging arm type supported by the. endcap and having a web portion and side flanges, a stud forminga pivot for tlm brush holder, a post, und a spring pressin against the brush holder and tl1e post, sai Web portion being constructed and arranged l'o lift the spring from the post when the brush holder waches a predeiermined angulmposition on the stud.

14.-. In a dynamo electrie machine, an ondcap, and a pressed-up sheet-metal brush holder of tho swinging arm type supported by the endcap and having a web portion integral with the side flanges and an end fiange, said end flange having a Hat outer Portion und said side flanges terminating in ears having holes, a brush faslened against the flat onter portion of the end flange, a stud supported by the endcap and passing throngzh l'ho holes in the ears, a post supported by the end cap, a double coiled sprin;

housed between the ears und having its ends pressing against tho brush holder und its intermediate portion pressing against the post, the end of said web portion being comstructed and arranged to lift the intermediate Portion of the spring ofi the stud when ehe brush holder reaches a predeterxnined angular position on the stud.

Intestimony whoreof I ture.

aflix my signa- LOUIS B. EHRLICH. 

